AISI D2 Tool Steel — Materials Encyclopedia Entry

AISI D2 is a high-carbon, high-chromium cold-work tool steel hardened by a population of large M₇C₃ primary carbides in a tempered martensite matrix. It is one of the most widely used blade materials in the converting, packaging and metalworking industries.

Standard composition (UNS T30402): C 1.40–1.60 %, Cr 11.0–13.0 %, Mo 0.70–1.20 %, V 0.50–1.10 %, Mn ≤ 0.60 %, Si ≤ 0.60 %, balance Fe.

Hardness: Annealed HB 220–255; hardened HRC 58–62 (typical), maximum practical HRC 64.

Heat treatment: Austenitise 1,020–1,050 °C, air cool, triple temper 510–530 °C, 2 h each. Sub-zero treatment (−80 °C) between first and second temper for tightest tolerances.

Properties: Excellent wear resistance from the M₇C₃ carbides. Moderate toughness (Charpy 18–28 J). Air-hardening with low distortion. Difficult to grind at high V content.

Applications: Paper and film slitter blades, shear blades on carbon steel ≤ 6 mm, granulator bed knives, crusher blades, knife-edge tooling. The default cold-work tool steel for industrial blades.

Cross-reference: ≈ JIS SKD11, DIN 1.2379, GB Cr12Mo1V1, BS BD2, AFNOR Z160CDV12, UNE F.5211. See the Material Grade Converter for the full table.

See also: D2 vs SKD11 comparison for the differences that matter in service, The KAIPU 5-Factor Blade Selection Framework for selection methodology.